mediawiki-extensions-Visual.../modules/ve/dm/ve.dm.Transaction.js
Roan Kattouw 6772f92e70 Get rid of 'reversed' flag on transactions
The way we implemented undoing transactions was horrible. We'd process
the original transaction, but with a reversed=true flag. That meant we
had to keep track of the 'reversed' flag everywhere, and use ternaries
like insert = reversed ? op.remove : op.insert; all over the place to
access transaction operations. Redo then worked by reapplying the
transaction. We would verify that this was OK by tracking whether the
transaction was in an applied state or an undone state.

This commit makes it so every transaction can only be applied once. To
undo, you obtain a mirror image of the transaction with tx.reverse(),
then apply that. To redo, you clone the original transaction with
tx.clone() and apply that. All the code that had to use ternaries to
check whether the transaction was being applied in reverse or not is
gone now, because you can only apply a given transaction forwards,
never in reverse.

Bonus:
* Make ve.dm.Document's .completeHistory a simple array of
  transactions, rather than transaction/boolean pairs
* In the protection of double application test, clone the example
  document properly; it modified ve.dm.example.data, which was "fine"
  because it ran .commit() and .rollback() the same number of times

Change-Id: I3050c5430be4a12510f22e20853560b92acebb67
2013-10-02 19:37:08 -07:00

1242 lines
43 KiB
JavaScript

/*!
* VisualEditor DataModel Transaction class.
*
* @copyright 2011-2013 VisualEditor Team and others; see AUTHORS.txt
* @license The MIT License (MIT); see LICENSE.txt
*/
/**
* DataModel transaction.
*
* @class
* @constructor
*/
ve.dm.Transaction = function VeDmTransaction() {
this.operations = [];
this.lengthDifference = 0;
this.applied = false;
};
/* Static Methods */
/**
* Generate a transaction that inserts data at an offset.
*
* @static
* @method
* @param {ve.dm.Document} doc Document to create transaction for
* @param {number} offset Offset to insert at
* @param {Array} data Data to insert
* @returns {ve.dm.Transaction} Transaction that inserts data
*/
ve.dm.Transaction.newFromInsertion = function ( doc, offset, data ) {
var insertion, tx = new ve.dm.Transaction();
// Fix up the insertion
insertion = doc.fixupInsertion( data, offset );
// Retain up to insertion point, if needed
tx.pushRetain( insertion.offset );
// Insert data
tx.pushReplace( doc, insertion.offset, insertion.remove, insertion.data );
// Retain to end of document, if needed (for completeness)
tx.pushFinalRetain( doc, insertion.offset + insertion.remove );
return tx;
};
/**
* Generate a transaction that removes data from a range.
*
* There are three possible results from a removal:
*
* - Remove content only
* - Occurs when the range starts and ends on elements of different type, depth or ancestry
* - Remove entire elements and their content
* - Occurs when the range spans across an entire element
* - Merge two elements by removing the end of one and the beginning of another
* - Occurs when the range starts and ends on elements of similar type, depth and ancestry
*
* This function uses the following logic to decide what to actually remove:
*
* 1. Elements are only removed if range being removed covers the entire element
* 2. Elements can only be merged if {@link ve.dm.Node#canBeMergedWith} returns true
* 3. Merges take place at the highest common ancestor
*
* @method
* @param {ve.dm.Document} doc Document to create transaction for
* @param {ve.Range} range Range of data to remove
* @returns {ve.dm.Transaction} Transaction that removes data
* @throws {Error} Invalid range
*/
ve.dm.Transaction.newFromRemoval = function ( doc, range ) {
var i, selection, first, last, nodeStart, nodeEnd,
offset = 0,
removeStart = null,
removeEnd = null,
tx = new ve.dm.Transaction();
// Validate range
if ( range.isCollapsed() ) {
// Empty range, nothing to remove, retain up to the end of the document (for completeness)
tx.pushFinalRetain( doc, 0 );
return tx;
}
// Select nodes and validate selection
selection = doc.selectNodes( range, 'covered' );
if ( selection.length === 0 ) {
// Empty selection? Something is wrong!
throw new Error( 'Invalid range, cannot remove from ' + range.start + ' to ' + range.end );
}
first = selection[0];
last = selection[selection.length - 1];
// If the first and last node are mergeable, merge them
if ( first.node.canBeMergedWith( last.node ) ) {
if ( !first.range && !last.range ) {
// First and last node are both completely covered, remove them
removeStart = first.nodeOuterRange.start;
removeEnd = last.nodeOuterRange.end;
} else {
// Either the first node or the last node is partially covered, so remove
// the selected content
removeStart = ( first.range || first.nodeRange ).start;
removeEnd = ( last.range || last.nodeRange ).end;
}
tx.pushRetain( removeStart );
tx.addSafeRemoveOps( doc, removeStart, removeEnd );
tx.pushFinalRetain( doc, removeEnd );
// All done
return tx;
}
// The selection wasn't mergeable, so remove nodes that are completely covered, and strip
// nodes that aren't
for ( i = 0; i < selection.length; i++ ) {
if ( !selection[i].range ) {
// Entire node is covered, remove it
nodeStart = selection[i].nodeOuterRange.start;
nodeEnd = selection[i].nodeOuterRange.end;
} else {
// Part of the node is covered, remove that range
nodeStart = selection[i].range.start;
nodeEnd = selection[i].range.end;
}
// Merge contiguous removals. Only apply a removal when a gap appears, or at the
// end of the loop
if ( removeEnd === null ) {
// First removal
removeStart = nodeStart;
removeEnd = nodeEnd;
} else if ( removeEnd === nodeStart ) {
// Merge this removal into the previous one
removeEnd = nodeEnd;
} else {
// There is a gap between the previous removal and this one
// Push the previous removal first
tx.pushRetain( removeStart - offset );
tx.addSafeRemoveOps( doc, removeStart, removeEnd );
offset = removeEnd;
// Now start this removal
removeStart = nodeStart;
removeEnd = nodeEnd;
}
}
// Apply the last removal, if any
if ( removeEnd !== null ) {
tx.pushRetain( removeStart - offset );
tx.addSafeRemoveOps( doc, removeStart, removeEnd );
offset = removeEnd;
}
// Retain up to the end of the document
tx.pushFinalRetain( doc, offset );
return tx;
};
/**
* Build a transaction that replaces the contents of a node with the contents of a document.
*
* This is typically used to merge changes to a document slice back into the main document. If newDoc
* is a document slice of doc, it's assumed that there were no changes to doc's internal list since
* the slice, so any differences between internal items that doc and newDoc have in common will
* be resolved in newDoc's favor.
*
* @param {ve.dm.Document} doc Main document
* @param {ve.Range|ve.dm.Node} removeNodeOrRange Node or range to remove
* @param {ve.dm.Document} newDoc Document to insert
* @returns {ve.dm.Transaction} Transaction that replaces the node and updates the internal list
* @throws {Error} removeNodeOrRange must be a ve.dm.Node or a ve.Range
*/
ve.dm.Transaction.newFromDocumentReplace = function ( doc, removeNodeOrRange, newDoc ) {
var i, len, range, merge, data, metadata, listData, listMetadata, oldEndOffset, newEndOffset,
listNode = doc.internalList.getListNode(),
listNodeRange = listNode.getRange(),
newListNode = newDoc.internalList.getListNode(),
newListNodeRange = newListNode.getRange(),
newListNodeOuterRange = newListNode.getOuterRange(),
tx = new ve.dm.Transaction();
if ( removeNodeOrRange instanceof ve.dm.Node ) {
range = removeNodeOrRange.getRange();
} else if ( removeNodeOrRange instanceof ve.Range ) {
range = removeNodeOrRange;
} else {
throw new Error( 'removeNodeOrRange must be a ve.dm.Node or a ve.Range' );
}
// Get the data and the metadata, but skip over the internal list
data = new ve.dm.ElementLinearData( doc.getStore(),
newDoc.getData( new ve.Range( 0, newListNodeOuterRange.start ), true ).concat(
newDoc.getData( new ve.Range( newListNodeOuterRange.end, newDoc.data.getLength() ), true )
)
);
metadata = new ve.dm.MetaLinearData( doc.getStore(),
newDoc.getMetadata( new ve.Range( 0, newListNodeOuterRange.start ), true ).concat(
// Merge the metadata immediately before and immediately after the internal list
ve.copy( ve.dm.MetaLinearData.static.merge( [
newDoc.metadata.getData( newListNodeOuterRange.start ),
newDoc.metadata.getData( newListNodeOuterRange.end )
] ) )
).concat( newDoc.getMetadata(
new ve.Range( newListNodeOuterRange.end, newDoc.data.getLength() ), true
) )
);
// Merge the stores
merge = doc.getStore().merge( newDoc.getStore() );
// Remap the store indexes in the data
data.remapStoreIndexes( merge );
merge = doc.internalList.merge( newDoc.internalList, newDoc.origInternalListLength || 0 );
// Remap the indexes in the data
data.remapInteralListIndexes( merge.mapping );
// Get data for the new internal list
if ( newDoc.origDoc === doc ) {
// newDoc is a document slice based on doc, so all the internal list items present in doc
// when it was cloned are also in newDoc. We need to get the newDoc version of these items
// so that changes made in newDoc are reflected.
if ( newDoc.origInternalListLength > 0 ) {
oldEndOffset = doc.internalList.getItemNode( newDoc.origInternalListLength - 1 ).getOuterRange().end;
newEndOffset = newDoc.internalList.getItemNode( newDoc.origInternalListLength - 1 ).getOuterRange().end;
} else {
oldEndOffset = listNodeRange.start;
newEndOffset = newListNodeRange.start;
}
listData = newDoc.getData( new ve.Range( newListNodeRange.start, newEndOffset ), true )
.concat( doc.getData( new ve.Range( oldEndOffset, listNodeRange.end ), true ) );
listMetadata = newDoc.getMetadata( new ve.Range( newListNodeRange.start, newEndOffset ), true )
.concat( doc.getMetadata( new ve.Range( oldEndOffset, listNodeRange.end ) , true ) );
} else {
// newDoc is brand new, so use doc's internal list as a base
listData = doc.getData( listNodeRange, true );
listMetadata = doc.getMetadata( listNodeRange, true );
}
for ( i = 0, len = merge.newItemRanges.length; i < len; i++ ) {
listData = listData.concat( newDoc.getData( merge.newItemRanges[i], true ) );
// We don't have to worry about merging metadata at the edges, because there can't be
// metadata between internal list items
listMetadata = listMetadata.concat( newDoc.getMetadata( merge.newItemRanges[i], true ) );
}
if ( range.end <= listNodeRange.start ) {
// range is entirely before listNodeRange
// First replace the node, then the internal list
tx.pushRetain( range.start );
tx.pushReplace( doc, range.start, range.end - range.start, data.data, metadata.data );
tx.pushRetain( listNodeRange.start - range.end );
tx.pushReplace( doc, listNodeRange.start, listNodeRange.end - listNodeRange.start,
listData, listMetadata
);
tx.pushRetain( doc.data.getLength() - listNodeRange.end );
} else if ( listNodeRange.end <= range.start ) {
// range is entirely after listNodeRange
// First replace the internal list, then the node
tx.pushRetain( listNodeRange.start );
tx.pushReplace( doc, listNodeRange.start, listNodeRange.end - listNodeRange.start,
listData, listMetadata
);
tx.pushRetain( range.start - listNodeRange.end );
tx.pushReplace( doc, range.start, range.end - range.start, data.data, metadata.data );
tx.pushRetain( doc.data.getLength() - range.end );
} else if ( range.start >= listNodeRange.start && range.end <= listNodeRange.end ) {
// range is entirely within listNodeRange
// Merge data into listData, then only replace the internal list
ve.batchSplice( listData, range.start - listNodeRange.start,
range.end - range.start, data.data );
ve.batchSplice( listMetadata, range.start - listNodeRange.start,
range.end - range.start + 1, metadata.data );
tx.pushRetain( listNodeRange.start );
tx.pushReplace( doc, listNodeRange.start, listNodeRange.end - listNodeRange.start,
listData, listMetadata
);
tx.pushRetain( doc.data.getLength() - listNodeRange.end );
}
return tx;
};
/**
* Generate a transaction that changes one or more attributes.
*
* @static
* @method
* @param {ve.dm.Document} doc Document to create transaction for
* @param {number} offset Offset of element
* @param {Object.<string,Mixed>} attr List of attribute key and value pairs, use undefined value
* to remove an attribute
* @returns {ve.dm.Transaction} Transaction that changes an element
* @throws {Error} Cannot set attributes to non-element data
* @throws {Error} Cannot set attributes on closing element
*/
ve.dm.Transaction.newFromAttributeChanges = function ( doc, offset, attr ) {
var key,
tx = new ve.dm.Transaction(),
data = doc.getData();
// Verify element exists at offset
if ( data[offset].type === undefined ) {
throw new Error( 'Cannot set attributes to non-element data' );
}
// Verify element is not a closing
if ( data[offset].type.charAt( 0 ) === '/' ) {
throw new Error( 'Cannot set attributes on closing element' );
}
// Retain up to element
tx.pushRetain( offset );
// Change attribute
for ( key in attr ) {
tx.pushReplaceElementAttribute(
key, 'attributes' in data[offset] ? data[offset].attributes[key] : undefined, attr[key]
);
}
// Retain to end of document
tx.pushFinalRetain( doc, offset );
return tx;
};
/**
* Generate a transaction that annotates content.
*
* @static
* @method
* @param {ve.dm.Document} doc Document to create transaction for
* @param {ve.Range} range Range to annotate
* @param {string} method Annotation mode
* - `set`: Adds annotation to all content in range
* - `clear`: Removes instances of annotation from content in range
* @param {ve.dm.Annotation} annotation Annotation to set or clear
* @returns {ve.dm.Transaction} Transaction that annotates content
*/
ve.dm.Transaction.newFromAnnotation = function ( doc, range, method, annotation ) {
var covered, type, annotatable,
tx = new ve.dm.Transaction(),
data = doc.data,
i = range.start,
span = i,
on = false,
insideContentNode = false;
// Iterate over all data in range, annotating where appropriate
while ( i < range.end ) {
if ( data.isElementData( i ) ) {
type = data.getType( i );
if ( ve.dm.nodeFactory.isNodeContent( type ) ) {
if ( method === 'set' && !ve.dm.nodeFactory.canNodeTakeAnnotationType( type, annotation ) ) {
// Blacklisted annotations can't be set
annotatable = false;
} else {
annotatable = true;
}
} else {
// Structural nodes are never annotatable
annotatable = false;
}
} else {
// Text is always annotatable
annotatable = true;
}
if (
!annotatable ||
( insideContentNode && !data.isCloseElementData( i ) )
) {
// Structural element opening or closing, or entering a content node
if ( on ) {
tx.pushRetain( span );
tx.pushStopAnnotating( method, annotation );
span = 0;
on = false;
}
} else if (
( !data.isElementData( i ) || !data.isCloseElementData( i ) ) &&
!insideContentNode
) {
// Character or content element opening
if ( data.isElementData( i ) ) {
insideContentNode = true;
}
covered = data.getAnnotationsFromOffset( i ).contains( annotation );
if ( ( covered && method === 'set' ) || ( !covered && method === 'clear' ) ) {
// Skip annotated content
if ( on ) {
tx.pushRetain( span );
tx.pushStopAnnotating( method, annotation );
span = 0;
on = false;
}
} else {
// Cover non-annotated content
if ( !on ) {
tx.pushRetain( span );
tx.pushStartAnnotating( method, annotation );
span = 0;
on = true;
}
}
} else if ( data.isCloseElementData( i ) ) {
// Content closing, skip
insideContentNode = false;
}
span++;
i++;
}
tx.pushRetain( span );
if ( on ) {
tx.pushStopAnnotating( method, annotation );
}
tx.pushFinalRetain( doc, range.end );
return tx;
};
/**
* Generate a transaction that inserts metadata elements.
*
* @static
* @method
* @param {ve.dm.Document} doc Document to create transaction for
* @param {number} offset Offset of element
* @param {number} index Index of metadata cursor within element
* @param {Array} newElements New elements to insert
* @returns {ve.dm.Transaction} Transaction that inserts the metadata elements
*/
ve.dm.Transaction.newFromMetadataInsertion = function ( doc, offset, index, newElements ) {
var tx = new ve.dm.Transaction(),
data = doc.metadata,
elements = data.getData( offset ) || [];
// Retain up to element
tx.pushRetain( offset );
// Retain up to metadata element (second dimension)
tx.pushRetainMetadata( index );
// Insert metadata elements
tx.pushReplaceMetadata(
[], newElements
);
// Retain up to end of metadata elements (second dimension)
tx.pushRetainMetadata( elements.length - index );
// Retain to end of document
tx.pushFinalRetain( doc, offset, elements.length );
return tx;
};
/**
* Generate a transaction that removes metadata elements.
*
* @static
* @method
* @param {ve.dm.Document} doc Document to create transaction for
* @param {number} offset Offset of element
* @param {ve.Range} range Range of metadata to remove
* @returns {ve.dm.Transaction} Transaction that removes metadata elements
* @throws {Error} Cannot remove metadata from empty list
* @throws {Error} Range out of bounds
*/
ve.dm.Transaction.newFromMetadataRemoval = function ( doc, offset, range ) {
var selection,
tx = new ve.dm.Transaction(),
data = doc.metadata,
elements = data.getData( offset ) || [];
if ( !elements.length ) {
throw new Error( 'Cannot remove metadata from empty list' );
}
if ( range.start < 0 || range.end > elements.length ) {
throw new Error( 'Range out of bounds' );
}
selection = elements.slice( range.start, range.end );
// Retain up to element
tx.pushRetain( offset );
// Retain up to metadata element (second dimension)
tx.pushRetainMetadata( range.start );
// Remove metadata elements
tx.pushReplaceMetadata(
selection, []
);
// Retain up to end of metadata elements (second dimension)
tx.pushRetainMetadata( elements.length - range.end );
// Retain to end of document (unless we're already off the end )
tx.pushFinalRetain( doc, offset, elements.length );
return tx;
};
/**
* Generate a transaction that replaces a single metadata element.
*
* @static
* @method
* @param {ve.dm.Document} doc Document to create transaction for
* @param {number} offset Offset of element
* @param {number} index Index of metadata cursor within element
* @param {Object} newElement New element to insert
* @returns {ve.dm.Transaction} Transaction that replaces a metadata element
* @throws {Error} Metadata index out of bounds
*/
ve.dm.Transaction.newFromMetadataElementReplacement = function ( doc, offset, index, newElement ) {
var oldElement,
tx = new ve.dm.Transaction(),
data = doc.getMetadata(),
elements = data[offset] || [];
if ( index >= elements.length ) {
throw new Error( 'Metadata index out of bounds' );
}
oldElement = elements[index];
// Retain up to element
tx.pushRetain( offset );
// Retain up to metadata element (second dimension)
tx.pushRetainMetadata( index );
// Remove metadata elements
tx.pushReplaceMetadata(
[ oldElement ], [ newElement ]
);
// Retain up to end of metadata elements (second dimension)
tx.pushRetainMetadata( elements.length - index - 1 );
// Retain to end of document (unless we're already off the end )
tx.pushFinalRetain( doc, offset, elements.length );
return tx;
};
/**
* Generate a transaction that converts elements that can contain content.
*
* @static
* @method
* @param {ve.dm.Document} doc Document to create transaction for
* @param {ve.Range} range Range to convert
* @param {string} type Symbolic name of element type to convert to
* @param {Object} attr Attributes to initialize element with
* @returns {ve.dm.Transaction} Transaction that converts content branches
*/
ve.dm.Transaction.newFromContentBranchConversion = function ( doc, range, type, attr ) {
var i, selected, branch, branchOuterRange,
tx = new ve.dm.Transaction(),
selection = doc.selectNodes( range, 'leaves' ),
opening = { 'type': type },
closing = { 'type': '/' + type },
previousBranch,
previousBranchOuterRange;
// Add attributes to opening if needed
if ( ve.isPlainObject( attr ) ) {
opening.attributes = attr;
} else {
attr = {};
}
// Replace the wrappings of each content branch in the range
for ( i = 0; i < selection.length; i++ ) {
selected = selection[i];
branch = selected.node.isContent() ? selected.node.getParent() : selected.node;
if ( branch.canContainContent() ) {
// Skip branches that are already of the target type and have identical attributes
if ( branch.getType() === type && ve.compare( branch.getAttributes(), attr ) ) {
continue;
}
branchOuterRange = branch.getOuterRange();
// Don't convert the same branch twice
if ( branch === previousBranch ) {
continue;
}
// Retain up to this branch, considering where the previous one left off
tx.pushRetain(
branchOuterRange.start - ( previousBranch ? previousBranchOuterRange.end : 0 )
);
// Replace the opening
tx.pushReplace( doc, branchOuterRange.start, 1, [ ve.copy( opening ) ] );
// Retain the contents
tx.pushRetain( branch.getLength() );
// Replace the closing
tx.pushReplace( doc, branchOuterRange.end - 1, 1, [ ve.copy( closing ) ] );
// Remember this branch and its range for next time
previousBranch = branch;
previousBranchOuterRange = branchOuterRange;
}
}
// Retain until the end
tx.pushFinalRetain( doc, previousBranch ? previousBranchOuterRange.end : 0 );
return tx;
};
/**
* Generate a transaction that wraps, unwraps or replaces structure.
*
* The unwrap parameters are checked against the actual model data, and
* an exception is thrown if the type fields don't match. This means you
* can omit attributes from the unwrap parameters, those are automatically
* picked up from the model data instead.
*
* NOTE: This function currently does not fix invalid parent/child relationships, so it will
* happily convert paragraphs to listItems without wrapping them in a list if that's what you
* ask it to do. We'll probably fix this later but for now the caller is responsible for giving
* valid instructions.
*
* Changing a paragraph to a header:
* Before: [ {'type': 'paragraph'}, 'a', 'b', 'c', {'type': '/paragraph'} ]
* newFromWrap( new ve.Range( 1, 4 ), [ {'type': 'paragraph'} ], [ {'type': 'heading', 'level': 1 } ] );
* After: [ {'type': 'heading', 'level': 1 }, 'a', 'b', 'c', {'type': '/heading'} ]
*
* Changing a set of paragraphs to a list:
* Before: [ {'type': 'paragraph'}, 'a', {'type': '/paragraph'}, {'type':'paragraph'}, 'b', {'type':'/paragraph'} ]
* newFromWrap( new ve.Range( 0, 6 ), [], [ {'type': 'list' } ], [], [ {'type': 'listItem', 'attributes': {'styles': ['bullet']}} ] );
* After: [ {'type': 'list'}, {'type': 'listItem', 'attributes': {'styles': ['bullet']}}, {'type':'paragraph'} 'a',
* {'type': '/paragraph'}, {'type': '/listItem'}, {'type': 'listItem', 'attributes': {'styles': ['bullet']}},
* {'type': 'paragraph'}, 'b', {'type': '/paragraph'}, {'type': '/listItem'}, {'type': '/list'} ]
*
* @param {ve.dm.Document} doc Document to generate a transaction for
* @param {ve.Range} range Range to wrap/unwrap/replace around
* @param {Array} unwrapOuter Opening elements to unwrap. These must be immediately *outside* the range
* @param {Array} wrapOuter Opening elements to wrap around the range
* @param {Array} unwrapEach Opening elements to unwrap from each top-level element in the range
* @param {Array} wrapEach Opening elements to wrap around each top-level element in the range
* @returns {ve.dm.Transaction}
*/
ve.dm.Transaction.newFromWrap = function ( doc, range, unwrapOuter, wrapOuter, unwrapEach, wrapEach ) {
var i, j, unwrapOuterData, startOffset, unwrapEachData, closingUnwrapEach, closingWrapEach,
tx = new ve.dm.Transaction(),
depth = 0;
// Function to generate arrays of closing elements in reverse order
function closingArray( openings ) {
var closings = [], i, len = openings.length;
for ( i = 0; i < len; i++ ) {
closings[closings.length] = { 'type': '/' + openings[len - i - 1].type };
}
return closings;
}
closingUnwrapEach = closingArray( unwrapEach );
closingWrapEach = closingArray( wrapEach );
// TODO: check for and fix nesting validity like fixupInsertion does
if ( range.start > unwrapOuter.length ) {
// Retain up to the first thing we're unwrapping
// The outer unwrapping takes place *outside*
// the range, so compensate for that
tx.pushRetain( range.start - unwrapOuter.length );
} else if ( range.start < unwrapOuter.length ) {
throw new Error( 'unwrapOuter is longer than the data preceding the range' );
}
// Replace the opening elements for the outer unwrap&wrap
if ( wrapOuter.length > 0 || unwrapOuter.length > 0 ) {
// Verify that wrapOuter matches the data at this position
unwrapOuterData = doc.data.slice( range.start - unwrapOuter.length, range.start );
for ( i = 0; i < unwrapOuterData.length; i++ ) {
if ( unwrapOuterData[i].type !== unwrapOuter[i].type ) {
throw new Error( 'Element in unwrapOuter does not match: expected ' +
unwrapOuter[i].type + ' but found ' + unwrapOuterData[i].type );
}
}
// Instead of putting in unwrapOuter as given, put it in the
// way it appears in the model so we pick up any attributes
tx.pushReplace( doc, range.start - unwrapOuter.length, unwrapOuter.length, ve.copy( wrapOuter ) );
}
if ( wrapEach.length > 0 || unwrapEach.length > 0 ) {
// Visit each top-level child and wrap/unwrap it
// TODO figure out if we should use the tree/node functions here
// rather than iterating over offsets, it may or may not be faster
for ( i = range.start; i < range.end; i++ ) {
if ( doc.data.isElementData( i ) ) {
// This is a structural offset
if ( !doc.data.isCloseElementData( i ) ) {
// This is an opening element
if ( depth === 0 ) {
// We are at the start of a top-level element
// Replace the opening elements
// Verify that unwrapEach matches the data at this position
unwrapEachData = doc.data.slice( i, i + unwrapEach.length );
for ( j = 0; j < unwrapEachData.length; j++ ) {
if ( unwrapEachData[j].type !== unwrapEach[j].type ) {
throw new Error( 'Element in unwrapEach does not match: expected ' +
unwrapEach[j].type + ' but found ' +
unwrapEachData[j].type );
}
}
// Instead of putting in unwrapEach as given, put it in the
// way it appears in the model, so we pick up any attributes
tx.pushReplace( doc, i, unwrapEach.length, ve.copy( wrapEach ) );
// Store this offset for later
startOffset = i + unwrapEach.length;
}
depth++;
} else {
// This is a closing element
depth--;
if ( depth === 0 ) {
// We are at the end of a top-level element
// Advance past the element, then back up past the unwrapEach
j = ( i + 1 ) - unwrapEach.length;
// Retain the contents of what we're wrapping
tx.pushRetain( j - startOffset );
// Replace the closing elements
tx.pushReplace( doc, j, unwrapEach.length, ve.copy( closingWrapEach ) );
}
}
}
}
} else {
// There is no wrapEach/unwrapEach to be done, just retain
// up to the end of the range
tx.pushRetain( range.end - range.start );
}
// this is a no-op if unwrapOuter.length===0 and wrapOuter.length===0
tx.pushReplace( doc, range.end, unwrapOuter.length, closingArray( wrapOuter ) );
// Retain up to the end of the document
tx.pushFinalRetain( doc, range.end + unwrapOuter.length );
return tx;
};
/**
* Specification for how each type of operation should be reversed.
*
* This object maps operation types to objects, which map property names to reversal instructions.
* A reversal instruction is either a string (which means the value of that property should be used)
* or an object (which maps old values to new values). For instance, { 'from': 'to' }
* means that the .from property of the reversed operation should be set to the .to property of the
* original operation, and { 'method': { 'set': 'clear' } } means that if the .method property of
* the original operation was 'set', the reversed operation's .method property should be 'clear'.
*
* If a property's treatment isn't specified, its value is simply copied without modification.
* If an operation type's treatment isn't specified, all properties are copied without modification.
*
* @type {Object.<string,Object.<string,string|Object.<string, string>>>}
*/
ve.dm.Transaction.reversers = {
'annotate': { 'method': { 'set': 'clear', 'clear': 'set' } }, // swap 'set' with 'clear'
'attribute': { 'from': 'to', 'to': 'from' }, // swap .from with .to
'replace': { // swap .insert with .remove and .insertMetadata with .removeMetadata
'insert': 'remove',
'remove': 'insert',
'insertMetadata': 'removeMetadata',
'removeMetadata': 'insertMetadata'
},
'replaceMetadata': { 'insert': 'remove', 'remove': 'insert' } // swap .insert with .remove
};
/* Methods */
/**
* Create a clone of this transaction.
*
* The returned transaction will be exactly the same as this one, except that its 'applied' flag
* will be cleared. This means that if a transaction has already been committed, it will still
* be possible to commit the clone. This is used for redoing transactions that were undone.
*
* @returns {ve.dm.Transaction} Clone of this transaction
*/
ve.dm.Transaction.prototype.clone = function () {
var tx = new this.constructor();
tx.operations = ve.copy( this.operations );
tx.lengthDifference = this.lengthDifference;
return tx;
};
/**
* Create a reversed version of this transaction.
*
* The returned transaction will be the same as this one but with all operations reversed. This
* means that applying the original transaction and then applying the reversed transaction will
* result in no net changes. This is used to undo transactions.
*
* @returns {ve.dm.Transaction} Reverse of this transaction
*/
ve.dm.Transaction.prototype.reversed = function () {
var i, len, op, newOp, reverse, prop, tx = new this.constructor();
for ( i = 0, len = this.operations.length; i < len; i++ ) {
op = this.operations[i];
newOp = ve.copy( op );
reverse = this.constructor.reversers[op.type] || {};
for ( prop in reverse ) {
if ( typeof reverse[prop] === 'string' ) {
newOp[prop] = op[reverse[prop]];
} else {
newOp[prop] = reverse[prop][op[prop]];
}
}
tx.operations.push( newOp );
}
tx.lengthDifference = -this.lengthDifference;
return tx;
};
/**
* Check if the transaction would make any actual changes if processed.
*
* There may be more sophisticated checks that can be done, like looking for things being replaced
* with identical content, but such transactions probably should not be created in the first place.
*
* @method
* @returns {boolean} Transaction is no-op
*/
ve.dm.Transaction.prototype.isNoOp = function () {
return (
this.operations.length === 0 ||
( this.operations.length === 1 && this.operations[0].type === 'retain' )
);
};
/**
* Get all operations.
*
* @method
* @returns {Object[]} List of operations
*/
ve.dm.Transaction.prototype.getOperations = function () {
return this.operations;
};
/**
* Check if the transaction has any operations with a certain type.
*
* @method
* @returns {boolean} Has operations of a given type
*/
ve.dm.Transaction.prototype.hasOperationWithType = function ( type ) {
var i, len;
for ( i = 0, len = this.operations.length; i < len; i++ ) {
if ( this.operations[i].type === type ) {
return true;
}
}
return false;
};
/**
* Check if the transaction has any content data operations, such as insertion or deletion.
*
* @method
* @returns {boolean} Has content data operations
*/
ve.dm.Transaction.prototype.hasContentDataOperations = function () {
return this.hasOperationWithType( 'replace' );
};
/**
* Check if the transaction has any element attribute operations.
*
* @method
* @returns {boolean} Has element attribute operations
*/
ve.dm.Transaction.prototype.hasElementAttributeOperations = function () {
return this.hasOperationWithType( 'attribute' );
};
/**
* Check if the transaction has any annotation operations.
*
* @method
* @returns {boolean} Has annotation operations
*/
ve.dm.Transaction.prototype.hasAnnotationOperations = function () {
return this.hasOperationWithType( 'annotate' );
};
/**
* Get the difference in content length the transaction will cause if applied.
*
* @method
* @returns {number} Difference in content length
*/
ve.dm.Transaction.prototype.getLengthDifference = function () {
return this.lengthDifference;
};
/**
* Check whether the transaction has already been applied.
*
* @method
* @returns {boolean}
*/
ve.dm.Transaction.prototype.hasBeenApplied = function () {
return this.applied;
};
/**
* Mark the transaction as having been applied.
*
* Should only be called after committing the transaction.
*
* @see ve.dm.Transaction#hasBeenApplied
*/
ve.dm.Transaction.prototype.markAsApplied = function () {
this.applied = true;
};
/**
* Translate an offset based on a transaction.
*
* This is useful when you want to anticipate what an offset will be after a transaction is
* processed.
*
* @method
* @param {number} offset Offset in the linear model before the transaction has been processed
* @param {boolean} [excludeInsertion] Map the offset immediately before an insertion to
* right before the insertion rather than right after
* @returns {number} Translated offset, as it will be after processing transaction
*/
ve.dm.Transaction.prototype.translateOffset = function ( offset, excludeInsertion ) {
var i, op, insertLength, removeLength, prevAdjustment, cursor = 0, adjustment = 0;
for ( i = 0; i < this.operations.length; i++ ) {
op = this.operations[i];
if ( op.type === 'replace' ) {
insertLength = op.insert.length;
removeLength = op.remove.length;
prevAdjustment = adjustment;
adjustment += insertLength - removeLength;
if ( offset === cursor + removeLength ) {
// Offset points to right after the removal or right before the insertion
if ( excludeInsertion && insertLength > removeLength ) {
// Translate it to before the insertion
return offset + adjustment - insertLength + removeLength;
} else {
// Translate it to after the removal/insertion
return offset + adjustment;
}
} else if ( offset === cursor ) {
// The offset points to right before the removal or replacement
if ( insertLength === 0 ) {
// Translate it to after the removal
return cursor + removeLength + adjustment;
} else {
// Translate it to before the replacement
// To translate this correctly, we have to use adjustment as it was before
// we adjusted it for this replacement
return cursor + prevAdjustment;
}
} else if ( offset > cursor && offset < cursor + removeLength ) {
// The offset points inside of the removal
// Translate it to after the removal
return cursor + removeLength + adjustment;
}
cursor += removeLength;
} else if ( op.type === 'retain' ) {
if ( offset >= cursor && offset < cursor + op.length ) {
return offset + adjustment;
}
cursor += op.length;
}
}
return offset + adjustment;
};
/**
* Translate a range based on a transaction.
*
* This is useful when you want to anticipate what a selection will be after a transaction is
* processed.
*
* @method
* @see #translateOffset
* @param {ve.Range} range Range in the linear model before the transaction has been processed
* @returns {ve.Range} Translated range, as it will be after processing transaction
*/
ve.dm.Transaction.prototype.translateRange = function ( range ) {
var start = this.translateOffset( range.start, true ),
end = this.translateOffset( range.end, false );
return range.isBackwards() ? new ve.Range( end, start ) : new ve.Range( start, end );
};
/**
* Add a final retain operation to finish off a transaction (internal helper).
*
* @private
* @method
* @param {ve.dm.Document} doc Document to finish off.
* @param {number} Final offset edited by the transaction up to this point.
* @param {number} [metaOffset=0] Final metadata offset edited, if nonzero.
*/
ve.dm.Transaction.prototype.pushFinalRetain = function ( doc, offset, metaOffset ) {
var data = doc.data,
metadata = doc.metadata,
finalMetadata = metadata.getData( data.getLength() );
if ( offset < doc.data.getLength() ) {
this.pushRetain( doc.data.getLength() - offset );
metaOffset = 0;
}
// if there is trailing metadata, push a final retainMetadata
if ( finalMetadata !== undefined && finalMetadata.length > 0 ) {
this.pushRetainMetadata( finalMetadata.length - ( metaOffset || 0 ) );
}
};
/**
* Add a retain operation.
*
* @method
* @param {number} length Length of content data to retain
* @throws {Error} Cannot retain backwards
*/
ve.dm.Transaction.prototype.pushRetain = function ( length ) {
if ( length < 0 ) {
throw new Error( 'Invalid retain length, cannot retain backwards:' + length );
}
if ( length ) {
var end = this.operations.length - 1;
if ( this.operations.length && this.operations[end].type === 'retain' ) {
this.operations[end].length += length;
} else {
this.operations.push( {
'type': 'retain',
'length': length
} );
}
}
};
/**
* Add a retain metadata operation.
* // TODO: this is a copy/paste of pushRetain (at the moment). Consider a refactor.
*
* @method
* @param {number} length Length of content data to retain
* @throws {Error} Cannot retain backwards
*/
ve.dm.Transaction.prototype.pushRetainMetadata = function ( length ) {
if ( length < 0 ) {
throw new Error( 'Invalid retain length, cannot retain backwards:' + length );
}
if ( length ) {
var end = this.operations.length - 1;
if ( this.operations.length && this.operations[end].type === 'retainMetadata' ) {
this.operations[end].length += length;
} else {
this.operations.push( {
'type': 'retainMetadata',
'length': length
} );
}
}
};
/**
* Adds a replace op to remove the desired range and, where required, splices in retain ops
* to prevent the deletion of internal data.
*
* An extra `replaceMetadata` operation might be pushed at the end if the
* affected region contains metadata; see
* {@link ve.dm.Transaction#pushReplace} for details.
*
* @param {ve.dm.Document} doc Document
* @param {number} removeStart Offset to start removing from
* @param {number} removeEnd Offset to remove to
*/
ve.dm.Transaction.prototype.addSafeRemoveOps = function ( doc, removeStart, removeEnd ) {
var i, retainStart, internalStackDepth = 0;
// Iterate over removal range and use a stack counter to determine if
// we are inside an internal node
for ( i = removeStart; i < removeEnd; i++ ) {
if ( doc.data.isElementData( i ) && ve.dm.nodeFactory.isNodeInternal( doc.data.getType( i ) ) ) {
if ( !doc.data.isCloseElementData( i ) ) {
if ( internalStackDepth === 0 ) {
this.pushReplace( doc, removeStart, i - removeStart, [] );
retainStart = i;
}
internalStackDepth++;
} else {
internalStackDepth--;
if ( internalStackDepth === 0 ) {
this.pushRetain( i + 1 - retainStart );
removeStart = i + 1;
}
}
}
}
this.pushReplace( doc, removeStart, removeEnd - removeStart, [] );
};
/**
* Add a replace operation, keeping metadata in sync if required.
*
* Note that metadata attached to removed content is moved so that it
* attaches just before the inserted content. If there is
* metadata attached to the removed content but there is no inserted
* content, then an extra `replaceMetadata` operation is pushed in order
* to properly insert the merged metadata before the character immediately
* after the removed content. (Note that there is an extra metadata element
* after the final data element; if the removed region is at the very end of
* the document, the inserted `replaceMetadata` operation targets this
* final metadata element.)
*
* @method
* @param {ve.dm.Document} doc Document model
* @param {number} offset Offset to start at
* @param {number} removeLength Number of data items to remove
* @param {Array} insert Data to insert
* @param {Array} [insertMetadata] Overwrite the metadata with this data, rather than collapsing it
*/
ve.dm.Transaction.prototype.pushReplace = function ( doc, offset, removeLength, insert, insertMetadata ) {
if ( removeLength === 0 && insert.length === 0 ) {
// Don't push no-ops
return;
}
var op, extraMetadata, end = this.operations.length - 1,
lastOp = end >= 0 ? this.operations[end] : null,
penultOp = end >= 1 ? this.operations[ end - 1 ] : null,
range = new ve.Range( offset, offset + removeLength ),
remove = doc.getData( range ),
removeMetadata = doc.getMetadata( range ),
isRemoveEmpty = ve.compare( removeMetadata, new Array( removeMetadata.length ) ),
isInsertEmpty = insertMetadata && ve.compare( insertMetadata, new Array( insertMetadata.length ) );
if ( !insertMetadata && !isRemoveEmpty ) {
// if we are removing a range which includes metadata, we need to
// collapse it. If there's nothing to insert, we also need to add
// an extra `replaceMetadata` operation later in order to insert the
// collapsed metadata.
insertMetadata = ve.dm.MetaLinearData.static.merge( removeMetadata );
if ( insert.length === 0 ) {
extraMetadata = insertMetadata[0];
insertMetadata = [];
} else {
// pad out at end so insert metadata is the same length as insert data
ve.batchSplice( insertMetadata, 1, 0, new Array( insert.length - 1 ) );
}
} else if ( isInsertEmpty && isRemoveEmpty ) {
// No metadata changes, don't pollute the transaction with [undefined, undefined, ...]
insertMetadata = undefined;
}
// simple replaces can be combined
// (but don't do this if there is metadata to be removed and the previous
// replace had a non-zero insertion, because that would shift the metadata
// location.)
if (
lastOp && lastOp.type === 'replaceMetadata' &&
lastOp.insert.length > 0 && lastOp.remove.length === 0 &&
penultOp && penultOp.type === 'replace' &&
penultOp.insert.length === 0 /* this is always true */
) {
this.operations.pop();
lastOp = penultOp;
/* fall through */
}
if (
lastOp && lastOp.type === 'replace' &&
!( lastOp.insert.length > 0 && insertMetadata !== undefined )
) {
lastOp = this.operations.pop();
this.lengthDifference -= lastOp.insert.length - lastOp.remove.length;
this.pushReplace(
doc,
offset - lastOp.remove.length,
lastOp.remove.length + removeLength,
lastOp.insert.concat( insert )
);
return;
}
if ( lastOp && lastOp.type === 'replaceMetadata' ) {
// `replace` operates on the metadata at the given offset; the transaction
// touches the same region twice if `replace` follows a `replaceMetadata`
// without a `retain` in between.
throw new Error( 'replace after replaceMetadata not allowed' );
}
op = {
'type': 'replace',
'remove': remove,
'insert': insert
};
if ( insertMetadata !== undefined ) {
op.removeMetadata = removeMetadata;
op.insertMetadata = insertMetadata;
}
this.operations.push( op );
this.lengthDifference += insert.length - remove.length;
if ( extraMetadata !== undefined ) {
this.pushReplaceMetadata( [], extraMetadata );
}
};
/**
* Add a replace metadata operation
*
* @method
* @param {Array} remove Metadata to remove
* @param {Array} insert Metadata to replace 'remove' with
*/
ve.dm.Transaction.prototype.pushReplaceMetadata = function ( remove, insert ) {
if ( remove.length === 0 && insert.length === 0 ) {
// Don't push no-ops
return;
}
this.operations.push( {
'type': 'replaceMetadata',
'remove': remove,
'insert': insert
} );
};
/**
* Add an element attribute change operation.
*
* @method
* @param {string} key Name of attribute to change
* @param {Mixed} from Value change attribute from, or undefined if not previously set
* @param {Mixed} to Value to change attribute to, or undefined to remove
*/
ve.dm.Transaction.prototype.pushReplaceElementAttribute = function ( key, from, to ) {
this.operations.push( {
'type': 'attribute',
'key': key,
'from': from,
'to': to
} );
};
/**
* Add a start annotating operation.
*
* @method
* @param {string} method Method to use, either "set" or "clear"
* @param {Object} annotation Annotation object to start setting or clearing from content data
*/
ve.dm.Transaction.prototype.pushStartAnnotating = function ( method, annotation ) {
this.operations.push( {
'type': 'annotate',
'method': method,
'bias': 'start',
'annotation': annotation
} );
};
/**
* Add a stop annotating operation.
*
* @method
* @param {string} method Method to use, either "set" or "clear"
* @param {Object} annotation Annotation object to stop setting or clearing from content data
*/
ve.dm.Transaction.prototype.pushStopAnnotating = function ( method, annotation ) {
this.operations.push( {
'type': 'annotate',
'method': method,
'bias': 'stop',
'annotation': annotation
} );
};